Nfasc186 (Neurofascin 186) is one of two alternatively spliced products of the Neurofascin (Nfasc) gene in rat; the other being Nfasc155. The establishment of paranodal axoglial junctions in myelinated nerves where voltage-gated sodium channels are concentrated at the nodes of Ranvier is determined by myelin-forming glia. The two isoforms of Neurofascin, Nfasc186 in neurons and Nfasc155 in glia, are required for the assembly of these specialized domains. These two major Neurofascins play essential roles in assembling the nodal and paranodal domains of myelinated axons and are essential for the transition to saltatory conduction in developing vertebrate nerves. Nfasc186 (Isoform 1) is expressed at the Nodes of Ranvier while the Nfasc155 (isoforms 2 and 3) are expressed in unmyelinated axons.

Cell Membrane; Type I membrane protein.